What is a Hydroponic Clone?
In botany a clone is a clipping of a plant that is removed and grown into another adult plant. This clone is a genetic copy of the parent plant. Cloning is used for a variety of farming needs, especially citrus and fruit growing where a perfect piece of fruit can be grown again and again. It’s a powerful tool used by gardeners worldwide.
The clones grow because each part of the plant contains instructions to regrow itself. If a plant falls over, the stem touching the ground can sprout roots and begin pushing new growth upright. Cloning exploits this phenomenon and the plant hormones that make it happen to create little copies. The two plants are genetic twins.
Cloning is for advanced hydroponic growers interested in maximizing their crop. It is not beginner friendly or even worth considering for first time hydroponics growers. This is because it requires to a mature, flourishing plant to use for the first generation.
Advantages to Hydroponic Cloning
Cloning offers growers a host of advantages compared to germinating plants from seeds. The greatest advantage of cloning is its output. Cloned plants mature faster and produce the quantity and quality of fruit or veggies that you want. Because cloning can be done over and over again, it’s a nearly foolproof way to get consistent results out of your plants. It’s ultimately cost effective.
Plants grown from seeds can fail to reach adulthood and will always take longer to reach a fruit-bearing age than clones. Cloning like what we’re discussing today is the mainstay of fruit growers throughout the world. Consistent, high-quality fruit comes often from clones of one specific parent plant generation after generation.
Disadvantages to Hydroponic Cloning
Cloning reduces your plants down to a single genetic identity. While those genes may get you the perfect harvest your looking for every time, it can also increase your crop’s susceptibility to disease. When all the plants you raise are actually one plant, a single disease, mold, or fungus can potentially wipe them all out. It’s putting your eggs into one basket. Genetic variety slows destructive invasions.
Also, a clone plant grows differently in one notable way than a plant grown from seeds. A clone plant will not send down a taproot like a germinating seed. It some ways a clone represents an upended plant. A plant in the wild will begin growing back upright if it falls over and show roots where the stem contacts the ground. Since we are turning an upper stem into new root location, this mimics what an upended plant in the wild would experience. The lack of a taproot is not a problem in hydroponics. Since the water is brought to the plant rather than the plant having to send a root out to find it, this downside is ignored.
Taking a clone does require more work than planting seeds. As the steps below will show, it’s more labor intensive than just jamming a seed in the ground and watering it. Additionally, each clone will have its sensitive, innermost layer exposed to air for a short time and this alone present risk to the plant.
Choosing a Plant to Clone
Plant growth is dictated by hormones within the plant carried by the stem between its root and top leaves. Plants uniquely carry the hormones they need for root growth throughout the entire plant. This means that cuttings from the top, when properly encouraged to release rooting hormone, will be able to regrow the entire plant. All that’s needed is water.
When to Clip?
We need to decide not just which plant to cut, but at which stage of its life cycle to clip cuttings from its stem. As the plant ages the hormones it releases changes. Plants grow in three stages. First, the vegetative stage is when the plant is building a root structure and stem to the correct size to transition into its later stages. The second stage is flowering as the plant prepares to reproduce itself. The final stage is a fruiting or harvest stage when the gardener either harvests the fruit or removes the plant entirely to eat it.
Since the plant is focused purely on expanding in the vegetation stage, it’s the ideal stage for taking a stem clipping from it. The plant is full of growth hormones and busy talking between its roots and leaves as it attempts to reach a correct height. Cuttings taken during this stage of plant growth are ideal for a clone.
A clone taken during flowering or harvest stage takes longer to root. The plant’s hormones change into making flowers or seeded fruit and no longer focuses purely on growth. Root growth is no longer a priority for the plant and the stem carries less root building hormones.
Selecting a mother plant to take clones from requires skill. Much of the output of the cloning process comes from selecting the best mother plant possible. Once selected the mother plant is kept in a perpetual vegetation state for the purpose of being used and resused as a source of clones.
A mother plant should be the best of the best. You will want to locate the strongest vegetative plant in your group. Many growers consider cloning to be a more advanced technique because it takes experience to select a correct mother plant. The fact that you want to take clippings from a plant which has not produced a harvest makes it a difficult choice. Experienced gardeners can select a correct plant, but only because of the years of learning they’ve acquired.
Once you’ve selected a mother plant, you want to make sure not to over-prune or over-clone it. Each clone will be cut from the stem so it’s important to care for the stem of the mother and know when you’re close to removing too much. Many hydroponic pros prefer to keep a mother plant soil-bound to maximize its stability and protect it. Soil can keep pH and nutrient content stabilized and the mother plant won’t be competing for nutrient solution from its children if it were kept in the same hydroponic system as them.
Also, consider replacing the mother in about a year with a clone of itself. This cycle of a year for a mother then replacing it with a clone can keep your harvest consistent year after year. Consistent harvests become the focus of gardeners the more years they grow. This technique has been found to be highly effective.
No Mother, No Worries
Additionally, you can take cuttings from each plant in a tray while they’re in a vegetation state to start a new batch of clones. This creates one genetic copy of each plant that has reached a healthy vegetative state. These cuttings can then become the next generation and replace their originators once they’ve developed far enough. This cycle can be repeated endlessly as each cycle creates new clones from the previous batch. Some hydroponic pros find this benefits their gardens and production without having to fuss over a single plant regularly.
Clipping a Clone
Once you’ve chosen which plant you will take your clone from, the next step is properly removing the portion of the plant you plan to grow. It’s crucial to make a proper cut in order to give the clone the best chances for survival.
Gather Supplies—What you’ll Need
- Scissors or a razor
- Hydrogen peroxide or rubbing alcohol
- A growing media
- Cloning gel
- A hydroponic cloning system
Sterilize your cutting tools with the rubbing alcohol or hydrogen peroxide. Be sure to also clean whatever hydroponic cloning system you will be placing the new clippings into. Think of it like surgery. The new clippings can easily get infected since the most sensitive part of the plant is exposed. The natural protections a plant uses to keep itself safe will be temporarily removed. Sterilizing keeps those tender, new plants safe.
Many hydroponic experts recommend conditioning the growing medium. This means soaking the medium in your nutrient solution 24 hours in advance if they are not the correct pH. Rockwool is a commonly recommended medium , but it’s too alkaline at first. You will need the rockwool to be turned more acidic for the health of your cuttings. Other growing mediums as well should be measured to ensure that their pH will not inhibit plant growth. The new cuttings will struggle to hold the right amount of water before they grow the proper roots to receive the water and placing them in a moist medium helps them transition smoothly.
Step 2—Snip the Snip
Once your tools are ready and the plant is in front of you, you’ll want to snip the stem in the right spot. The term ‘node’ describes the location on the stem of a plant where a new growth branches from the stalk. You’ll want to cut below internodal growth. This means you cut the stem just above a lower node. The length of stem on your cuttings will be secured in your medium to grow and root as a brand new clone. Be sure to clip the plant at a 45 degree angle. This exposes more of the inner layer which the plant will use to send out a new root system.
Your cuttings should have a main leaf, a smaller leaf, and a node or newly forming leaf. Alternatively, the cut should contain 3-4 medium sized leaves and enough stem to extend down stably into the medium.
The growth layer of the plant is called the Cambium layer. If you’ve down your cut correctly, it will expose this layer to air. The Cambium layer is what will extend the roots out into the environment to gather water and nutrients for the new clipping. It’s this that we will want to immediately protect with one of our other items—our gel.
Step 3—Dip the Clone in Cloning Gel
A cloning gel—another name for this product is rooting powder—will jump start the root growing process. This gel generally comes in small containers resembling cosmetics containers and run around twenty bucks or less. They’re a vital part of the cloning process. Dip the fresh cut in the gel before planting it. This gel protects the plant from infection while also dousing it in plant hormones telling it to grow roots. Sometimes these products are also called rooting gel. The plant will generate its own hormones to tell the cut stem to grow roots, but with the gel this process happens quicker which keeps the new clone from taking too long to root and dying.
Step 4—Remove Excess Foliage
If the clipping you’ve cut contains too many large leaves, those leaves will compete with resources the plant would use to send out roots. We don’t want that. Leaves require a lot of resources from the plant that it no longer has access to until the clone regrows its root system. It may seem paradoxical to cut leaves off a clone you want to grow, but it will only need a few key leaves in its first stage of growth. When you take cuttings of foliage, you encourage the clone to spend its energy growing roots—the only way it will survive the transition and reach maturity.
Making Happy Little Clones
A new clone starts its life in crisis mode. It’s just lost an entire plant worth of support and resources. In order to survive it’ll need proper setup in a hydroponic tray or bucket and proper light. The first few days are delicate, but if the clone makes it a week and a root shows, it will likely make it to full maturity since it was taken from an already healthy plant.
Planting the Clones
Stick the stem of each gel-coated clipping into the stonewool or other growing medium and then into your net cups. We will hopefully be able to fill every hole in our tray to maximize our clone production. This is why it’s possible to over-prune a mother plant because the goal of getting a clone into every net cup may ignore the health of the mother when that many cuttings are removed. Most hydroponic trays have 9-14 holes for net cups. Assuming you’re using a tray or bucket, fill each net cup now.
If you are using a deep water culture, you will want the water level to be close to the bottom of the cups but not inundating the new plants. Aeroponic systems don’t contain a water level that needs to be monitored, but other hydroponic systems will.
Cloning trays are also sometimes called cloning machines. This so called ‘machine’ is usually just a tray that is sold together with a water pump or air pump. These trays include everything necessary to care for your cuttings so no other purchase is necessary.
A major reason for clone failure is that the clone doesn’t receive proper conditions to transition from their delicate state of new clipping to a healthy, independent plant. To maximize clone health and growth potential we’ll need to consider their environment.
Air Temperature 75-80 Degrees
Warmer air temperatures reduce evaporation. Plants lose water immediately after being cut off from their mother plant. Warm temperatures help the plant conserve water since the plants essentially perspire less in warmer and more humid air, but be careful. Too much heat and the new plant will suffer.
Humidity makes sure that the clones don’t lose too much water through their leaves. Avoiding water loss keeps the clones from drying out before their roots begin providing water. Since hydroponics is based entirely around water and a nutrient solution, the humidity of the grow area will always be a concern.
This amount of humidity can be difficult to reach in a closet or garage. It’s possible to purchase a propagator lid which covers the tray in a clear, hard plastic cover to increase the humidity the plants live in. This humidity is not a requirement but helps achieve an optimal growing environment. Depending on your setup it may be difficult to achieve specific humidity percentages, or if you live on the coast, you may have this humidity perpetually.
Root Temperature 75-80 Degrees
To promote root growth, having a higher temperature at the bottom of the clone than the top can enlist it to grow better. Consider a thin heat pad as a part of your cloning setup. This pad can be set under your hydroponic tray or bucket and will warm the bottom of each clone. But be careful. Hotter water temperatures reduce the amount of oxygen in the water and the root system of a clone should not go above 82 degrees.
Proper lighting tells the new clone to grow and get on with photosynthesis. You will want your clones to get 18 hours of light for the first few days. 24 hours of light might seem like a way to accelerate growth, but it may result in stressing a clone. 6 hours of darkness per day has been found my many hydroponic veterans to be the optimal amount for a new clone.
If you’re only using daylight, then you won’t have this option. Most light setups will work fine for new clones, but you may want to soften the light the first few days. The new clones are at their most sensitive the first 48 hours and excel when they’ve got soft light the first few days.
Crucial First Few Days
Keep all of the temperatures in the ranges described as best you can. Make sure there is enough moisture in the growing medium as the plant will use its exposed stem and leaves to take in water before roots form. Test to make sure that the pH correctly sits between 5.8-6.3 pH. The pH will have a tendency to rise. In the very first few days, the plants need water but not nutrient solution. No roots means no needs for nutrients at first.
Try using a softer light for the first 2 days. This can be accomplished by using a thin cloth over the top of the propagator, but a softer light protects them from an an otherwise harsh first few days on their own.
Your clones should show the first sign of new roots around the 7 day mark. Different types of plants will show roots at different days so it’s important to be patient. Once roots begin to show you can gradually reduce the humidity the clones are in. Once the plants have rooted and reached the fourteenth day, they can be transitioned into your normal grow room alongside other plants. Shifting them gradually to the temperatures and humidity of your other plants is a good idea. Sudden changes could shock them and cause the entire process to be wasted. The good news is that once you begin to notice the roots reaching out, you’ve already succeeded as a gardener. It’s time for the plants to take over—with supervision, of course.
It’s time to add nutrient solution. Dilute it at first if you can. Continue to monitor the pH and EC numbers. A weaker EC is fine at first since the solution is dilute. Correct pH and EC numbers remain vital in all parts of hydroponics and must be monitored constantly to succeed.
Nutrient Strength for Clones
Clones require less nutrients at first since they’ve come directly from the stem of a larger plant full of nutrients. Water without any nutrient solution can be used at first with new clones. Since the clippings have no root system, they have no way to draw nutrients from the water at first. They only need to be able to keep themselves from drying out. Once a root system begins to show a diluted bloom nutrient can be used.
When the clones show good roots, they can be moved to grow alongside the other plants and eat similar contents to their mother or parent plants. The only difference a growing clone shows to a germinated seed is the lack of a taproot. Clones don’t produce a taproot, but when they’re cared for hydroponically, they don’t need to use a taproot to find water. With hydroponics, the water is brought to them.
Hydroponic Cloning Solution
This solution is similar to typical plant nutrient solutions. Chemically, there is little difference between a cloning solution and a plant nutrient solution. The same nutrients exist in both in similar quantities. More important than the solution you buy is observing and maintaining proper pH and PPM readings.
If your nutrient content gets too far out of a range your cuttings need, you’ll have problems quickly. In hydroponic systems, the new cuttings depend entirely on the nutrient solution and will fade quickly if not properly cared for. Make sure you begin your process with an pH up or down product to adjust the nutrient solution’s pH as needed.
Aeroponic cloning is a variant of hydroponics. The only difference is that the clones will be watered with mist rather than water. Aeroponic systems use an arrangement of spray nozzles to deliver the water to the clones. This makes sure the roots of the plant never drown while receiving the correct quantity of water. Whether hydroponic or aeroponic, a pump will be used to deliver water to the roots before it drains away.
The downside of aeroponics comes from the fact that the spray nozzles can get clogged over time. The amount of minerals in the nutrient solution will cause build up over time. The nozzles need regular cleaning. Additionally, if the water pump is located within the container, it can get too hot and harm the plants.
Best Cloning Trays and Buckets
A variety of affordable trays and buckets exist. You can make your own tray with a drill, a drill attachment, and a five gallon bucket lid or a ten gallon plastic tote lid. Making containers for your own cuttings is great if you don’t want to put a lot of money into your project or search online.
The nice thing about buying a bucket cloner kit from amazon or other stores is that you don’t have to worry about purchasing any other parts of the system. Kits on amazon run around $50-80 and include all nutrients, pumps, net cups, growing mediums, testers, and more. They come with everything but the cuttings.
Additionally, you’ll have to decide if you want a aeroponic setup up of a hydroponic setup. Cloning trays and buckets can be used for either but your choice will change the insides of the container. Clones can thrive in either of the cloners, but they do take different pumps and water levels. The nutrient ratios will be the same in either system.
Help—My Clones are Dead!
Hydroponics can be unforgiving. The plants depend entirely on a correct nutrient solution, so if there’s something off in the solution they will die. Sometimes with little warning. If your clones die repeatedly, make sure the medium you’re placing them in is adequately prepared. You medium can be a silent killer if it’s too alkaline or inhibiting the plants in another fashion. The good news is that hydroponics is a closed system and you will be able to locate what’s harming your plants. It’s only one of three things—the nutrient solution, the medium it’s sitting in, or the lighting situation.
How can I Tell if they’re Stunted or Not?
Really the best way to know a slow-grower from a regular grower will be experience. Once you’re familiar enough with the type of plant you have and have seen them root many times, you will be able to discover this by observation. If a plant is not growing well, it is often down to the root system not expanding fast enough to provide nutrients to the whole plant.
Even if you’ve done your homework, success with hydroponic cloning takes practice. Expect to improve bit by bit. The pros weren’t pros in a day. Even if the worst happens, don’t let a few dead plants keep you from enjoying your garden. Just pick up where you left off. It’s worth the effort.